The maid company is oddly suspicious, not in a bad way. Afai can see;
1. The owner and manager is an Oujo-chan hailing from a wealthy family and came from an all girl school.
2. The maids working there are an odd bunch. By their behavior and love to smoke; two of them at least behaved like an ex-girl gang members. But maid-san have classical training in music. Suggesting similiar background in upbringing to the owner/oujo san.
3. All of the maids and the owner are behaving as if they were in a rough spot before with some clients and now are strictly protective of each others, regards their contract with highest priority and not seeing having to call someone "master" as something as degrading.